This invention relates to a chewing gum providing an improved sweetness and flavor and a method of preparing the same and more particularly to an improvement of the chewing gum with an amino-carbonyl reaction product.
As used herein, the term of "amino-carbonyl reaction" means a browning phenomenon, commonly known as Maillard reaction or melanoidine reaction caused between amino acids and sugars (especially reducing sugars).
As sweeteners for a chewing gum, hitherto have been used naturally occurring sugars such as sucrose, glucose, fructose, inverted sugar, maltose and others; sugar alcohols such as sorbitol, xylitol, maltitol and others for a sugarless chewing gum; and synthetic sweeteners such as saccharin, cyclamate, glycyrrhizin and others for strengthening sweetness. Recently, a new naturally occurring sweetener such as stebioside has been employed in view of the health reason and the sweentening quality. Further, it has been well-known that the naturally occurring sugar, especially sucrose or inverter sugar is most favorable in view of the sweetening quality or the fondness of sweetness, and sugar molasses or inverted sugar provides higher sweetness and better taste for foods than most pure granulated sugar.
In consideration of the health reason as described hereinbefore, however, have been produced various types of chewing gum products, for example so-called sugarless chewing gums which employ sorbitol, saccharin, glycyrrhizin, stebioside for strengthening deficient sweetness in limited amount of digestible natural sugars or utilize sugar alcohols for substitution of the natural sugars. Such substitution or strengthening might reduce or eliminate an intrinsic good taste of sugar in the chewing gum product. Thus, there is need for food additives which provide a good quality and taste of sweetness for a low-sugar or sugarless chewing gum.
In general, a heated flavor of sugar has been considered to appear due to a component showing a roasted sugar note, such as furfral which is formed by partial decomposition of sugar upon heat treatment. The roasted sugar note could be caused by reaction of sugars with amino acids as well. Maltol, which is well-known as a food additive, shows also the sugar note.
On the other hand, it has been well-known that a browning phenomenon or Maillard reaction occurs between sugars and amino acids to form furfral derivatives, N-Glycosides and reductants which in turn provide the unique taste for food.
For example, Kremers (1948) produced an imitation maple flavoring by heating sugars with .alpha.-aminobutyric acid, .alpha.-aminoisobutyric acid, serine, threonine, and other .alpha.-amino acids of three to six carbon atoms. Rusoff (1958) produced an artificial chocolate flavor by heating a reducing sugar with a glycyl or alanyl peptide at 130.degree. C. for eight minutes. Bitterness was supplied by adding an alkaloid, such as theobromine or caffeine, and astringency was introduced by adding quebracho or chestnut tannins. General Foods Corporation (1963) made flavors resembling chocolate, coffee, or tea by autoclaving mixtures of wheat bran and peanut flour with sugar and water for only a few minutes near 200 pC. Morton and Sharples (1959) made a honey-flavored syrup by refluxing glucose with .beta.-phenylalanine in water. This reaction was known to give a floral scent, like wilted roses (Ruckdeschel 1914), but they added invert sugar syrup containing citric and glutamic acids to enhance the honey flavor. Labahov and Kerebinski (1958) reported a mushroom-flavored mixture that was formed by heating glucose with sodium glutamate for 1.25 hr. at 195.degree. C. A yeast-free, chemically-leavened "Instant Bread Mix," developed by the Quartermaster Corps for use by the Armed Forces, gave a good-textured bread that had only a raw, starchy taste. Flavor for the bread was easily synthesized, however, by use of the Maillard reaction. Ruckdeschel (1914) had shown that glucose and leucine when heated together produced a bready aroma. Kiely et al. (1960) added only 0.05 to 0.10% leucine to the Instant Bread Mix, which already contained glucose, and thereby produced by baking a toasted bread-like aroma. The further addition of histidine or arginine added buttery notes and gave the finished bread an acceptable flavor. Keeney and Day (1957) incubated milk protein hydrolyzates with pyruvic acid, isating, or ninhydrin for 18 hr. at room temperature and then distilled out cheese-like aromas. A small amount of such a distillate, when added to cottage cheese, produced a Cheddar-type flavor. These practical accomplishments are based on a fundamental chemical reaction that is only one part of the total Maillard complex.
The Maillard reaction product or amino-carbonyl product, however, has never been used for improving the quality of sweetness in the chewing gums, especially the sugarless chewing gums.
The inventors have now found out that if amino-carbonyl reaction product is formed in a chewing gum base in the presence of amino acids and sugars under the condition for preparing the gum base a chewing gum prepared from the gum base has an excellent quality of sweetness and a good taste.
This effect is more significant for the sugarless chewing gum using only sugar alcohols as sweeteners. Further, it has been found out that the effect is enhanced if the amino-carbonyl product is formed in the gum base in the coexistence of maltol and/or protein hydrolzate. As used herein, the term of "protein hydrolyzate" means a mixture of all amino acid compounds including various simple amino acids through oligopeptides to polypeptides formed by hydrolysis of protein.
In view of the result as described hereinbefore, the inventors have further found out that preparation of the amino-carbonyl reaction product separately from the gum base and its incorporation thereinto in a predetermined amount may also significantly improve the quality of sweetness and the flavor and taste. Similarly, in the case of separate preparation of the amino-carbonyl reaction product, the coexistence of maltol and/or protein hydrolyzate results in the enhanced effect.